We use expo's social authentication mechanism for using facebook and google sign in. For other types of sign in like Github and Twitter, We are using WebView architecture explained here.
For facebook, You would just need to configure facebookScheme,facebookDisplayName,facebookAppId under app/app.json. On how to get these please follow the setups here under Configuration section.
Please note for facebook authentication to work in release builds, make sure to add facebook hashes as explained in the above link.
For google sign in Please follow below steps :